Köves K, Molnár J
Neuroendocrinology. 1986;44(2):172-83. doi: 10.1159/000124642.
Various supra- and retrochiasmatic cuts injuring different parts of the septo-preoptico-infundibular GnRH pathway were made in adult female rats, and their effects on ovulation, median eminence (ME) GnRH content and on plasma LH and FSH levels were studied. Extended retrochiasmatic frontal cut just behind the optic chiasm, or a frontal cut in front of the suprachiasmatic nucleus presumably interrupting the whole GnRH pathway blocked ovulation, led to persistent estrus with polyfollicular ovaries, and reduced the ME GnRH content to 10 and 32%, respectively, expressed in percentage of unoperated control value. Severance of the GnRH pathway on one side or partial interruption of the pathway on the two sides in the retrochiasmatic area did not interfere with ovulation, and the ME GnRH content was 50% or more of the control value. Disconnection of the GnRH fibers coming from the septum resulted in a more than 30% decrease in the GnRH content of the ME, but did not block ovulation. Two separate symmetrical lateral cuts in the suprachiasmatic area leaving intact the presently known GnRH pathway reduced the ME GnRH content to 40% of the intact value, but did not interfere with ovulation. Plasma LH and FSH levels of the animals with different knife cuts were considerably dissociated and there were no apparent correlations between brain interventions and the concentrations of these two hormones in the blood. Our previous findings together with the present data suggest that: half of the GnRH pathway, medial or lateral bundles of the pathway on the two sides are sufficient for ovulation and cyclic gonadotrophic function; persistent estrus develops if the ME GnRH content is below 40% of the control value, and about 60% of the ME GnRH originates outside the preoptic, supra- and retrochiasmatic region. Half of this 60% may come from the septum and the vertical part of the diagonal band of Broca, the other half from the region in front of the preoptic area. The remaining 40% presumably arises from the preoptic (7-10%), supra- (15-20%) and retrochiasmatic region (8-10%).
在成年雌性大鼠中，对隔区 - 视前区 - 漏斗部促性腺激素释放激素（GnRH）通路的不同部位进行了各种视交叉上和视交叉后的切割，并研究了其对排卵、正中隆起（ME）GnRH含量以及血浆促黄体生成素（LH）和促卵泡生成素（FSH）水平的影响。在视交叉后方紧邻处进行扩展的视交叉后额状切割，或在视交叉上核前方进行额状切割，推测这会中断整个GnRH通路，从而阻断排卵，导致持续发情并伴有多囊卵巢，并且使ME GnRH含量分别降至未手术对照值的10%和32%（以百分比表示）。在视交叉后区域一侧切断GnRH通路或两侧部分中断该通路并不影响排卵，且ME GnRH含量为对照值的50%或更高。切断来自隔区的GnRH纤维导致ME的GnRH含量下降超过30%，但并未阻断排卵。在视交叉上区域进行两个单独的对称横向切割，使目前已知的GnRH通路保持完整，这将ME GnRH含量降至完整值的40%，但并未干扰排卵。接受不同切割的动物的血浆LH和FSH水平有很大差异，并且脑部干预与血液中这两种激素的浓度之间没有明显的相关性。我们之前的研究结果与当前数据表明：GnRH通路的一半，即两侧通路的内侧或外侧束，足以实现排卵和周期性促性腺功能；如果ME GnRH含量低于对照值的40%，则会出现持续发情，并且大约60%的ME GnRH起源于视前区、视交叉上和视交叉后区域之外。这60%中的一半可能来自隔区和布罗卡斜带的垂直部分，另一半来自视前区前方的区域。其余40%可能源自视前区（7 - 10%）、视交叉上区（15 - 20%）和视交叉后区域（8 - 10%）。
